Statement I: Hard water does not give lather with soap. Statement II: Calcium and magnesium salts, present in hard Abater form precipitate with soap.

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Q: 69 (NDA-I/2013)
Statement I: Hard water does not give lather with soap.
Statement II: Calcium and magnesium salts, present in hard Abater form precipitate with soap.

question_subject: 

Science

question_exam: 

NDA-I

stats: 

0,18,6,18,3,0,3

keywords: 

{'lather': [0, 0, 0, 1], 'hard water': [0, 0, 0, 2], 'soap': [0, 0, 0, 3], 'magnesium salts': [0, 0, 2, 1], 'calcium': [2, 0, 0, 4], 'hard abater form': [0, 0, 0, 1]}

Option 1, "Both the statements are individually true and Statement II is the correct explanation of Statement I," is the correct answer.

Statement I states that hard water does not give lather with soap. This is true because hard water contains high levels of calcium and magnesium ions, which react with the soap to form insoluble precipitates. These precipitates do not allow the soap to form lather or spread evenly on the skin or clothes.

Statement II explains why hard water does not give lather with soap. It states that the calcium and magnesium salts present in hard water form precipitates with soap. Again, this is true because the calcium and magnesium ions in hard water react with the soap, resulting in the formation of insoluble soap scum or curd.

Hence, both statements are true, and Statement II correctly explains why hard water does not give lather with soap.